Enchant Slashing Weapon.
The Caster runs the blade along their hand, suffering the weapons dice damage (i.e. 1d8 if enchanting a longsword). The enchanted weapon counts as magical and ignores slashing resistance for the duration of the enchantment. It also counts as a +1 weapon, if it does not already have such a bonus. It also gains Vorpal properties.
When you attack a creature that has at least one head with this weapon and roll a 20 on the attack roll, you cut off one of the creature's heads. The creature dies if it can't survive without the lost head. A creature is immune to this effect if it is immune to slashing damage, doesn't have or need a head, has legendary actions, or the GM decides that the creature is too big for its head to be cut off with this weapon. Such a creature instead takes an extra 6d8 slashing damage from the hit.
* - (Caster's blood)
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